The Lotus japonicus Genome

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Background and History of the Lotus

japonicusModel Legume System

Jens Stougaard

Abstract

The combination of favourable biological features, stable transformation

procedures, application of genetics and genome-based global approaches

has established Lotus japonicusas a model legume and provided a

platform for addressing important biological questions often, but not

exclusively, focusing on endosymbiosis. Several important discoveries

have been made, and theLotuscommunity has contributed novel results,

promoting our understanding of plant biology as well as our understand-

ing of properties and characteristics typical for plants belonging to the

legume family. Progress has been fast since L. japonicus was first

promoted as a model plant yet there are many challenges for the coming

years. This introductory chapter will set the stage for some of these

challenges, while possibilities and challenges emerging from specific

research projects will be addressed in the chapters that follow.

1.1 TheLotus japonicusModel
Legume System

Mendel worked with garden peas for his
groundbreaking work that established genetics as
a science (Reid and Ross 2011 ). For many years,
pea plants were also the workhorse in classical
plant physiology. The ethylene-induced triple
response of pea seedlings was, for example, one
of the key observations leading to the

identification of ethylene as a plant hormone.

Continuing the genetic approaches, large collec-

tions of pea mutants and morphological variants

were isolated, and substantial effort was invested

in their phenotypic characterisation. Included in

this collection was a sizeable subset of symbiotic

plant mutants, with phenotypes ranging from

non-nodulation to hypernodulation (Borisov

et al. 2007 ; Tsyganov et al. 2002 ). From a his-

torical perspective, the need for a model legume

may therefore not have been obvious when the

quest for a model legume started. However,

prospects for combining genetics with stable

transformation and emerging methodologies for

genome-based studies inspired a search for a

legume better suited to these global approaches.

One of the outcomes was the proposal ofLotus

japonicusas a model legume in 1992 (Handberg

J. Stougaard (&)
Centre for Carbohydrate Recognition and Signalling,
Department of Molecular Biology and Genetics,
Aarhus University, Gustav Wieds Vej 10,
8000 Aarhus C, Denmark
e-mail: [email protected]

S. Tabata and J. Stougaard (eds.),The Lotus japonicus Genome, Compendium of Plant Genomes,
DOI 10.1007/978-3-662-44270-8_1,©Springer-Verlag Berlin Heidelberg 2014

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